IELTS Writing Task 1: How to Describe a Chart

In IELTS Academic Writing Task 1 you describe a visual such as a bar chart, line graph, table, pie chart, map or process diagram. You have about 20 minutes and must write at least 150 words. Task 2 carries more weight in your Writing score, but a weak Task 1 can still pull your band down. This lesson focuses on charts and graphs, the most common visual.

What the examiner is looking for

Task 1 is marked on four criteria: Task Achievement, Coherence and Cohesion, Lexical Resource and Grammatical Range and Accuracy. For Task Achievement, the single most important feature is a clear overview: a summary of the main trends or differences. A response without an overview will usually struggle to move above Band 5 for this criterion, no matter how many numbers it includes.

You do not need to give your opinion or explain why the data changed. Report only what the chart shows.

A simple four-paragraph structure

1. Introduction (1–2 sentences): paraphrase the task. Change the words, do not copy the question.
2. Overview (2–3 sentences): the biggest trends or comparisons, with no or very few numbers.
3. Body paragraph 1: details of one group of data, with figures.
4. Body paragraph 2: details of another group, with figures and comparisons.

Some writers put the overview at the end as a conclusion. Both positions are acceptable, but placing it second makes sure you never forget it.

Grouping the data

Do not describe every bar or line one by one. Instead, group the data in a logical way:

• Categories that rose vs categories that fell
• The largest items vs the smallest
• The start of the period vs the end
• Items that crossed over each other

Grouping is what separates a Band 5 list of numbers from a Band 7 summary.

Language for trends and comparisons

Trends (line graphs, changes over time):

• rose / increased / climbed / grew steadily / sharply / slightly
• fell / declined / dropped / decreased
• remained stable / levelled off / fluctuated
• peaked at... / reached a low of...

Comparisons (bar charts, tables):

• X was twice as high as Y.
• X accounted for the largest share, at 40%.
• By contrast, / Whereas...
• Only slightly more than...

Approximation: just under a third, roughly half, nearly 60%.

Be careful with percent vs percentage points. A change from 20% to 30% is a rise of 10 percentage points, which is actually a 50% increase.

Worked example

Imagine an invented bar chart showing the average weekly hours that students at a college spent on part-time work, study and social media in 2016 and 2024.

• Study: 22 → 18 hours
• Part-time work: 6 → 11 hours
• Social media: 9 → 17 hours

Weak overview: Study was 22 hours and then 18 hours. Work was 6 and then 11. (This is just a list of numbers.)

Strong overview: Overall, students devoted less time to study in 2024 than in 2016, while the hours spent on both paid work and social media rose considerably, with social media almost catching up with study by the end of the period.

Body sentence with a comparison: Time on social media nearly doubled, from 9 to 17 hours a week, whereas study time fell by 4 hours to 18.

Hitting 150 words sensibly

Aim for 160–190 words. Fewer than 150 words may be penalised, but writing 300 words wastes time you need for Task 2 and increases the chance of errors. A practical guide:

• Introduction: about 25 words
• Overview: about 35 words
• Each body paragraph: about 50–60 words

Common mistakes

• No overview. This is the most costly error.
• Copying the question. Copied words are not counted towards your word total and show limited vocabulary.
• Giving reasons or opinions ("This is because people became lazier").
• Using the wrong tense. For past years, use the past simple. For future projections, use is expected to or is predicted to.
• Listing every figure without comparison.
• Wrong units. If the chart shows thousands of tonnes, do not write "tonnes".

Closing tip

Before you write a single sentence, spend two or three minutes looking at the chart and asking: "What would I tell someone in one sentence about this?" That sentence is your overview. Write it first in your head, and the rest of the report will organise itself around it.